The present invention relates to gripping means for use in the withdrawal of tubular members from support means.
In an example of use of the means of the present invention, to which it is in no way limited, a multiplicity of tubular members is received in a plurality of support walls comprising a heat exchanger, evaporator or condenser. After a period of service the tubular members require replacement and a method of replacing them is described in our co-pending application Ser. No. 870,212 now U.S. Pat. No. 4,161,810.
In a typical example, a hollow adapter is fixed to a leading edge of the tubular member to be replaced and a gripping device is applied to the adapter to pull it and the tubular member out from the support walls using a stepwise action. This pulling action is enhanced if the preliminary stage is carried out whilst a trailing edge of the tubular member is firmly held in the rear support wall so that pulling the tubular member is drawn in a manner to reduce its diameter and break any corrosion bonds between it and the intermediate walls.
However, it not infrequently occurs that the trailing edge of the tubular member is so firmly fixed in the rear support wall that it is extremely difficult to free it in the manner described. It is therefore necessary on occasions to apply a pulling action in an opposite direction to free the member.